易截截图软件、单文件、免安装、纯绿色、仅160KB

如何提高Mysql语句插入性能

在表中已有大量的index的情况下插入大量数据,可以采用先将索引删除,然后再插入数据,然后再重新建立索引。之所以这样会快是因为???
7.2.14 Speed of INSERT Statements
The time to insert a record is determined by the following factors, where the numbers indicate approximate proportions:
    * Connecting: (3)
    * Sending query to server: (2)
    * Parsing query: (2)
    * Inserting record: (1 x size of record)
    * Inserting indexes: (1 x number of indexes)
    * Closing: (1)
This does not take into consideration the initial overhead to open tables, which is done once for each concurrently running query.
The size of the table slows down the insertion of indexes by log N, assuming B-tree indexes.
You can use the following methods to speed up inserts:
    * If you are inserting many rows from the same client at the same time, use INSERT statements with multiple VALUES lists to insert several rows at a time. This is much faster (many times faster in some cases) than using separate single-row INSERT statements. If you are adding data to a non-empty table, you may tune the bulk_insert_buffer_size variable to make it even faster. See section 5.2.3 Server System Variables.
    * If you are inserting a lot of rows from different clients, you can get higher speed by using the INSERT DELAYED statement. See section 14.1.4 INSERT Syntax.
    * With MyISAM tables you can insert rows at the same time that SELECT statements are running if there are no deleted rows in the tables.
    * When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using a lot of INSERT statements. See section 14.1.5 LOAD DATA INFILE Syntax.
    * With some extra work, it is possible to make LOAD DATA INFILE run even faster when the table has many indexes. Use the following pr


相关文档:

Mysql中找不到.myd文件的问题

Wordpress用了这么长时间,偶尔会想起来备份下数据,上次是用wp的xml,这次把自己机器的环境配的跟主机提供商基本一样了,正好那边有mysql数据库打包备份的服务,就尝试了一下。可不管我下载哪个时间点的备份包,里面都只有wp表的10个frm文件,copy到我的数据库目录后访问web,没有任何数据!直接搞不懂了。以前觉得用mysql ......

Linux 下自动备份MYSQL数据库的shell 脚本

MySQL :: Linux 下自动备份数据库的 shell 脚本
Linux 服务器上的程序每天都在更新 MySQL 数据库,于是就想起写一个 shell 脚本,结合 crontab,定时备份数据库。其实非常简单,主要就是使用 MySQL 自带的 mysqldump 命令。
脚本内容如下:
#!/bin/sh
# File: /home/mysql/backup.sh
# Database info
DB_NAME=" ......

mysql在红旗linux下全程安装配置祥解

1、下载MySQL的安装文件
安装MySQL需要下面两个文件:
MySQL-server-5.0.46.i386.rpm   
MySQL-client-5.0.46.i386.rpm

2、安装MySQL
rpm文件是Red Hat公司开发的软件安装包,rpm可让Linux在安装软件包时免除许多复杂的手续。该命令在安装时常用的参数是
ivh
,其中i表示将安装指定的rmp软件包,V表 ......

使MySQL root账户能远程访问

1.登录MySQL终端 2.授权:
允许所有机器访问MySQL服务器
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'IDENTIFIED BY 'password' WITH GRANT OPTION;
FLUSH RIVILEGES;
允许指定机器访问MySQL服务器
GRANT ALL PRIVILEGES ON *.* TO 'root'@'IP地址'IDENTIFIED BY 'password' WITH GRANT OPTION; ......

Mysql Innodb 引擎优化(


参数篇
作/译者:吴炳锡,来源:http://imysql.cn & http://imysql.cn/blog/3208 转载请注明作/译者和出处,并且不能用于商业用途,违者必究。
 
介绍:
  InnoDB给MySQL提供了具有提交,回滚和崩溃恢复能力的事务安全(ACID兼容)存储引擎。InnoDB锁定在行级并且也在SELECT语句提供一个Oracle风格一致 ......
© 2009 ej38.com All Rights Reserved. 关于E健网联系我们 | 站点地图 | 赣ICP备09004571号